中文摘要：

异质性企业贸易模型是新新贸易理论的基本分析框架,该模型从企业生产率异质性角度分析企业出口的决定因素,得到企业拥有高生产率是保证其出口的重要条件,从而出口企业的生产率要高于内销企业的结论。不过,对中国企业的经验研究却发现,出口企业的生产率未必高于内销企业,甚至低于内销企业,即中国出口企业存在＂生产率悖论＂。目前,对于＂生产率悖论＂的研究主要集中于经验分析,并没有提出一个合理解释该现象的理论模型。文章从扩展异质性企业贸易模型的角度,建立了一个旨在解释＂生产率悖论＂的数理模型。尽管该模型对＂生产率悖论＂具有解释作用,但是并没有否定生产率对企业出口的作用。文章进一步使用较新的LP方法计算了中国制造业企业的生产率并运用统计法检验了出口企业＂生产率悖论＂的存在性,检验结果表明中国制造业大部分行业不存在＂生产率悖论＂。总之,文章研究认为生产率只是企业出口的一个必要条件而不是充分条件,这也重新构建了新新贸易理论的分析框架。

英文摘要：

The heterogeneous-firms trade model is the basic analytical framework of new-new trade theory,which analyzes the determinants of corporate export from the angle of corporate productivity heterogeneity and arrives at a conclusion that high productivity is an important condition of corporate export and thus the productivity of exporters is higher than the one of non-exporters.However,empirical studies of Chinese firms show that the productivity of exporters is not necessarily higher than the one of non-exporters and is even lower,namely there is a productivity paradox in Chinese exporters.Currently,the research on productivity paradox focuses on empirical studies,and does not provide a theoretical model which can reasonably explain this phenomenon.This paper extends the heterogeneous-firms trade model and establishes a mathematical model,which plays a role in explaining the productivity paradox but does not repudiate the effect of productivity on corporate export.Furthermore,it employs LP method to calculate the productivity of manufacturers in China and tests the existence of productivity paradox in Chinese exporters by statistical methods.The results show that there is no productivity paradox in most manufacturing industries in China.In short,this paper suggests that the productivity is a necessary but not sufficient condition of corporate export,leading to the reconstruction of analytical framework of new-new trade theory.